Ultrathin conformal coatings for electrostatic dissipation in semiconductor process tools

ABSTRACT

Disclosed in some embodiments is a chamber component (such as an end effector body) coated with an ultrathin electrically-dissipative material to provide a dissipative path from the coating to the ground. The coating may be deposited via a chemical precursor deposition to provide a uniform, conformal, and porosity free coating in a cost effective manner. In an embodiment wherein the chamber component comprises an end effector body, the end effector body may further comprise replaceable contact pads for supporting a substrate and the contact surface of the contact pads head may also be coated with an electrically-dissipative material.

RELATED APPLICATIONS

This application claims priority to Indian Provisional PatentApplication No. 201941038863, filed Sep. 26, 2019, which is hereinincorporated by reference in its entirety.

TECHNICAL FIELD

Embodiments of the present disclosure relate generally to coatedsemiconductor process tools (such as an apparatus for transferringobjects in a processing system), electrically-dissipative coatings, andmethods for depositing such coatings. In certain embodiments, thepresent disclosure relates to an end effector of a robot arm coated withan electrically-dissipative material.

BACKGROUND

In electronic device manufacturing, substrates (e.g., silicon-containingwafers, silicon-containing plates) may be moved about manufacturingfacilities and within manufacturing equipment tools by robots. Therobots can include robot arms having one or more end effectors coupledthereto that may contact and support the substrates during suchtransportation. End effectors include contact pads thereon that provideelevated contact surfaces upon which the substrates are supported.

SUMMARY OF THE DISCLOSURE

In certain embodiments, the instant disclosure may be directed to acoated chamber component comprising a chamber component and a coatingdeposited on a surface of the chamber component. In certain embodiments,the coating may comprise an electrically-dissipative material. Theelectrically-dissipative material may provide a dissipative path fromthe coating to the ground. The coating may be uniform, conformal, andporosity free. The coating may have a thickness ranging from about 10 nmto about 900 nm and an electrical surface/sheet resistance ranging fromabout 1×10⁵ ohm/sq to about 1×10¹¹ ohm/sq.

In certain embodiments, the instant disclosure may be directed to amethod comprising depositing a coating onto a surface of a chambercomponent using an atomic layer deposition (ALD) process, a chemicalvapor deposition (CVD) process, a plasma enhanced atomic layerdeposition (PEALD) process, a metal organic chemical vapor deposition(MOCVD), or a molecular beam epitaxy (MBE) process. The coating maycomprise an electrically-dissipative material. Theelectrically-dissipative material may provide a dissipative path fromthe coating to ground. The coating may be uniform, conformal, porosityfree, have a thickness ranging from about 10 nm to about 900 nm, and anelectrical surface/sheet resistance ranging from about 1×10⁵ ohm/sq toabout 1×10¹¹ ohm/sq.

In certain embodiments, the instant disclosure may be directed to anelectrically-dissipative coating comprising an electrically-dissipativematerial. The coating may be uniform, conformal, porosity free, have athickness ranging from about 10 nm to about 900 nm, and an electricalsurface/sheet resistance ranging from about 1×10⁵ ohm/sq to about 1×10¹¹ohm/sq.

In certain embodiments, the instant disclosure may be directed to an endeffector for a robot arm. The end effector may comprise an end effectorbody and a coating deposited on the surface of the end effector body.The coating may comprise an electrically-dissipative material. Theelectrically-dissipative material may provide a dissipative path fromthe coating to the ground. The coating may be uniform, conformal, andporosity free. The coating may have a thickness ranging from about 10 nmto about 900 nm. The coating may have an electrical surface/sheetresistance ranging from about 1×10⁵ ohm/sq to about 1×10¹¹ ohm/sq.

In certain embodiments, the instant disclosure may be directed to amethod. The method may comprise depositing a coating onto a surface ofan end effector for a robot arm using an atomic layer deposition (ALD)process, a chemical vapor deposition (CVD) process, a plasma enhancedatomic layer deposition (PEALD) process, a metal organic chemical vapordeposition (MOCVD), or a molecular beam epitaxy (MBE) process. Thecoating may comprise an electrically-dissipative material. Theelectrically dissipative material may provide a dissipative path fromthe coating to the ground. The coating may be uniform, conformal, andporosity free. The coating may have a thickness ranging from about 10 nmto about 900 nm. The coating may have an electrical surface/sheetresistance ranging from about 1×10⁵ ohm/sq to about 1×10¹¹ ohm/sq.

In certain embodiments, the instant disclosure may be directed to asubstrate processing system. The substrate processing system maycomprise a chamber, a robot disposed in the chamber, and a robot armconnected to the robot. The robot arm may comprise an end effector body,a replaceable contact pad, and a coating. The replaceable contact padmay be disposed on the end effector body. The replaceable contact padmay comprise a contact pad head having a contact surface configured tocontact a substrate, and a shaft coupled to the contact pad head andreceived in an aperture formed in the body of the end effector andextending into a recess. The coating may be deposited on a surface ofthe end effector body and on the contact surface of the contact padhead. The coating may comprise an electrically-dissipative material. Theelectrically dissipative material may provide a dissipative path fromthe coating to the ground. The coating may be uniform and conformal.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawings in which likereferences indicate similar elements. It should be noted that differentreferences to “an” or “one” embodiment in this disclosure are notnecessarily to the same embodiment, and such references mean at leastone.

FIG. 1 illustrates a perspective view of an example of an end effectorincluding one or more contact pads provided in accordance with anembodiment of the present disclosure.

FIG. 2 depicts a side view of a coated end effector body in accordancewith an embodiment of the present disclosure.

FIG. 3 illustrates a partial cross-sectional view taken along section2A-2A of FIG. 1 of a portion of an end effector including a replaceablecontact pad in accordance with embodiments of the present disclosure.

FIG. 4 depicts an atomic layer deposition process that may be used tocoat an end effector body for a robot arm or another chamber componentin accordance with embodiments of the present disclosure.

FIG. 5 depicts an exemplary chamber for a chemical vapor depositionprocess that may be used to coat an end effector body for a robot arm oranother chamber component in accordance with embodiments of the presentdisclosure.

FIG. 6 illustrates a top schematic view of an electronic devicemanufacturing apparatus including a transfer robot having an endeffector including replaceable contact pads that may be together coatedin accordance with one or more embodiments of the present disclosure.

FIG. 7A depicts an EDS line scan of a coating according to an embodimentof the present disclosure.

FIG. 7B depicts a TEM image at 50 nm scale of the coating depicted inFIG. 7A.

FIG. 8 depicts the electrical surface/sheet resistance of a coatingaccording to an embodiment as a function of pressure.

FIGS. 9A and 9B depict images of the front and back, respectively, of anexemplary end effector coated with a coating according to an embodiment.The sheet resistance values measured in each of the locations identifiedare summarized in Table 1.

FIGS. 10A and 10B depicts images of the front and back, respectively, ofan exemplary bulk-doped ceramic end effector. The sheet resistancevalues measured in each of the locations identified are summarized inTable 2.

DETAILED DESCRIPTION

In electronic device manufacturing processes, substrates (e.g., siliconwafers, silicon-containing plates, etc.) configured to produceelectronic components (e.g., electronic chips or electronicsubcomponents thereof) are moved, often via use of one or more robots,through a number of manufacturing steps. The robots include endeffectors that support the substrates during such movements. Movingsubstrates very quickly can increase throughput and reduce manufacturingcosts of the produced electronic components.

However, the rapid movement of robots when transporting substrates mayalso generate charged particles that can gather on surfaces and in turncontribute to substrate defects. Such substrate defects may be minimizedby coating surfaces that tend to become charged (such as an end effectorof a robot arm) with an electrically-dissipative coating. Theelectrically-dissipative coating may assist in releasing the charge fromthe surface, allowing the particles to break free of van der vaalsforces and re-distribute. The electrically-dissipative coatings may beable to support electrostatic discharge and avoid arcing and othersudden conductive events between a charged chamber component surface(e.g., a charged end effector body) and/or wafer thereon and othersystem components.

The instant disclosure encompasses various embodiments relating toelectrically-dissipative coatings, methods for depositing suchelectrically-dissipative coatings, chamber components coated withelectrically-dissipative coatings, an end effector body coated withelectrically-dissipative coatings, and a substrate processing systemutilizing components (e.g., chamber components and/or substratetransport components (such as end effectors)) that are coated with suchelectrically-dissipative coatings. In some embodiments, theelectrically-dissipative coatings are also plasma resistant coatings.

The coating processes described herein may be advantageous and costeffective as they may utilize bare chamber components (such as endeffector bodies) that are more readily available, face lessmanufacturing and yield issues, have shorter lead times, and so on.Furthermore, a plurality of chamber components (such as end effectorbodies) may be coated simultaneously (e.g., by inserting a plurality ofend effector bodies into the ALD, CVD, PEALD, MOCVD, or MBE depositionchamber). The resulting coating may also be more uniform, moreconformal, have lower porosity, be stronger, maintain its integritylonger (even under extreme conditions such as vacuum, thermal shock,thermal cycling, and so on), and have a narrower distribution ofelectrical surface/sheet resistivities, as compared to chambercomponents manufactured by other processes (such as bulk ceramic dopingprocesses and slurry-based coating processes).

In an exemplary embodiment, the instant disclosure may be directed to acomponent for transporting substrates coated with a coating havingcertain properties. In one embodiment, the component for transportingsubstrates may be an end effector for a robot arm. The coating may havedissipative properties and may comprise an electrically-dissipativematerial to provide an electrically-dissipative path from the coating tothe ground. The coating may be uniform, conformal, and porosity free.The coating may have a thickness ranging from about 10 nm to about 900nm (e.g., about 20 nm to about 500 nm). The coating may have anelectrical surface/sheet resistance ranging from about 1×10⁵ ohm/sq toabout 1×10¹¹ ohm/sq.

The body of the component for transporting substrates may comprise aninsulator or a conductor, such as, without limitations, a ceramic, anelectrically-conductive material (such as a metal), a polymer, quartz,and so on. In one embodiment, the body of the component for transportingsubstrates may comprise a material suitable for high temperatureprocesses, such as quartz. Quartz may be suitable for high temperatureprocesses due to its transparency, which permits radiation to go throughit while having minimal thermal effect on the substrate that is beingtransported. The coating deposited on the component may retain some ofthe properties of the material of construction of the underlyingcomponent. For instance, the coating may retain the transparency of anunderlying quartz component to maintain the minimal thermal effect on asubstrate. In certain embodiments, the coating deposited on thecomponent may have certain properties that are independent of theproperties of the material of construction of the underlying component.For instance, the resistivity performance of the coating may beindependent of the underlying component.

The coating may be a bilayer stack or a plurality of alternating layersstack. The coating may comprise a variety of materials and may beselected, among other factors, based on the target properties of thefinal coating (e.g., electrically-dissipative properties, transparency,thermal-conductivity, corrosion resistance, hardness, thermal shockresistance, thermal cycling resistance, vacuum resistance, scratchadhesion, wear rate, purity, roughness, conformality, and so on). Incertain embodiments, the coating may comprise a stack of alternatinglayers of a first material-containing layer and a secondmaterial-containing layer. The thickness ratio of the thickness of eachfirst material-containing layer to the thickness of each secondmaterial-containing layer may range from about 50:1 to about 1:50. Inone embodiment, the bilayer stack or the alternating layer stack mayinclude one or more of alumina and titania. The thickness ratio of thethickness of each alumina layer to the thickness of each titania layermay range from about 10:1 to about 1:10.

In certain embodiments, the component for transporting substrates thatis being coated may be an end effector. The end effector body maycomprise replaceable contact pads thereon for reducing and/oreliminating slipping of a substrate from the surface of the end effectorduring transport. In one embodiment, the replaceable contact pads may becoated along with the end effector with any of the coatings describedherein using any of the coating methods described herein. Alternatively,or additionally, the replaceable contact pads may be composed of anelectrically-dissipative material.

The coating described herein may be deposited via an atomic layerdeposition (ALD) process, via a chemical vapor deposition (CVD) process,via an plasma enhanced atomic layer deposition (PEALD) process, via ametal organic chemical vapor deposition (MOCVD) process, via a molecularbeam epitaxy (MBE) process, and other similar chemical precursordeposition processes. Coatings that comprise more than one layer and/ormore than one metal may be deposited through sequential deposition,through co-deposition, or through co-dosing of precursors.

ALD (and optionally CVD, PEALD, MOCVD and/or MBE) may be suitabledeposition methods in this disclosure due to their ability to uniformlyand conformally coat components having complex three dimensionalfeatures, holes, large aspect ratios, and so on. Additionally with thesecoating processes, a plurality of bare components (e.g. end effectors)that have not been coated (e.g., bare bulk alumina that has not beendoped with titania) may be placed in a deposition chamber and coatedsimultaneously. The cheaper starting material, the ability to coat aplurality of chamber components simultaneously, and the flexibility andability to optimize the coating process, among other factors, providefor a more cost efficient process and ultimately a more affordablecoated component.

As used herein, the singular forms “a,” “an,” and “the” include pluralreferences unless the context clearly indicates otherwise. Thus, forexample, reference to “a wafer” includes a single wafer as well as amixture of two or more wafers; and reference to a “metal” includes asingle metal as well as a mixture of two or more metals, and the like.

As used herein, the term “about” in connection with a measured quantity,refers to the normal variations in that measured quantity, as expectedby one of ordinary skill in the art in making the measurement andexercising a level of care commensurate with the objective ofmeasurement and the precision of the measuring equipment. In certainembodiments, the term “about” includes the recited number ±10%, suchthat “about 10” would include from 9 to 11.

Recitation of ranges of values herein are merely intended to serve as ashorthand method of referring individually to each separate valuefalling within the range, unless otherwise indicated herein, and eachseparate value is incorporated into the specification as if it wereindividually recited herein. All methods described herein can beperformed in any suitable order unless otherwise indicated herein orotherwise clearly contradicted by context. The use of any and allexamples, or exemplary language (e.g., “such as”) provided herein, isintended merely to illuminate certain materials and methods and does notpose a limitation on scope. No language in the specification should beconstrued as indicating any non-claimed element as essential to thepractice of the disclosed materials and methods.

As used herein, the term “plasma resistant” means resistant to one ormore types of plasma as well as resistant to chemistry and radicalsassociated with the one or more types of plasma.

Certain embodiments are discussed herein with reference to an endeffector that is coated with an electrically-dissipative coating.However, it should be understood that the electrically-dissipativecoating described in embodiments herein may also be used to coat othercomponents of processing chambers, transfer chambers, factory interfacechambers, load locks, load ports, slit valves, and so on. Accordingly,the electrically-dissipative coatings described herein may coat anycomponent of an electronic device processing tool or system. Someexamples of such components include a substrate support assembly, anelectrostatic chuck, a gas delivery plate, a lid, a nozzle, a liner, aring (e.g., a process kit ring or single ring), a base, a showerhead,gas lines, a liner kit, a shield, a plasma screen, a flow equalizer, acooling base, a chamber viewport, a chamber lid, and so on.

FIG. 1 depicts a first example embodiment of a chamber component thatmay be coated with the electrically-dissipative coating describedherein. In FIG. 1 , the exemplary chamber component is an end effector100 configured to support a substrate 101 (a portion thereof showndotted). The end effector 100 may be made up of an end effector body 102having a top surface 102T (FIG. 2 ) and a bottom surface 102B. The topsurface 102T may comprise a plane containing three spot faces that areraised above an underlying planar surface 102PS of the end effector body102. The end effector body 102 may be configured to couple orinterconnect to a robot component at an inboard end 1041, such as to arobot arm (e.g., robot wrist 653—see FIG. 6 ). Coupling may be by way offasteners (not shown) received through bores 105 thus coupling the endeffector 100 to the robot arm (e.g., wrist 653). Coupling may be madedirectly to the wrist member 653 or through and intermediate componentsuch as a mounting plate 654 (FIG. 6 ) in order to reduce cracking ofthe end effector 100 when made from a ceramic or glass material.

An outboard end 1040 of the end effector body 102 can includes firstfork 107A and second fork 107B, each of which can be configured toreceive and support a contact pad 108 thereon. In some embodiments, thecontact pads 108 are composed of an electrically-dissipative material orare coated with an electrically-dissipative material. The contact pads108 on the outboard end 1040 and a third contact pad 108 proximate theinboard end 1041 can provide for stable three-point contact supportingthe substrate 101 thereon (only a portion of substrate 101 shown inFIGS. 1 and 2 ). Substrate 101 can be supported on the contact pads 108of the end effector 100 between an inboard shelf 1091, which may be anarcuate step of approximately a same radius as the substrate 101, andoutboard shelves 1090. Spacing between the respective inboard shelves1091 and outboard shelves 1090 can be slightly larger (e.g., a few mm)than the substrate 101, such as where dimension 111 may be a diameterthat is slightly larger than 300 mm in diameter or 450 mm in diameter orother dimension of the substrate 101. Other configurations of the endeffector body 102 other than shown can be used. The end effector 102and/or contact pads 108 may be coated with an electrically-dissipativecoating in embodiments.

FIG. 2 is a side view of exemplary end effector body 102 depictingbottom surface 102B, top surface 102T, inboard shelf 1091, outboardshelf 1090, and a coating 200 deposited on top surface 102T. Thedimensions of the end effector body 102 and coating 200 may be not toscale and are depicted in FIG. 2 for illustrative purposes only. Contactpads 108 are not depicted in FIG. 2 . While the coating 200 is describedherein as being deposited on the top surface (102T) of end effector body102, coating 200 may also be deposited on the top surface of otherchamber components even if not explicitly recited herein. Exemplarychamber components that may be coated with electrically-dissipativecoating 200 may include transfer chambers, factory interface chambers,load locks, load ports, slit valves, and so on.

The end effector body 102 can be manufactured from a rigid material. Insome embodiments, the end effector body 102 may be made of a stable,lightweight material that reduces the end effector's deflection undervarying chamber processing conditions including pressure andtemperature. Suitable, non-limiting, materials for the end effector body102 include insulating material or conductive materials, such as,without limitations, a polymer, glass, quartz, ceramic, or a conductivematerial (such as a metal material).

For example, a ceramic such as bulk alumina can be used. In someembodiments, suitable ceramics may be semi-conductive to facilitate thedischarge of any electrostatic charge that may build up on thesubstrate. Other semi-conductive ceramic materials include, for example,alumina-SiC composites, SiC, silicon nitride, boron nitride, and boron.In certain embodiments, the coating 200 disclosed herein contributes tothe semi-conductive properties of a coated end effector body (or of anycoated chamber component). The semi-conductive properties may avoid ahigh conductance that can result in arcing between the coated chambercomponent (e.g., end effector) and other system components. Thesesemi-conductive properties may also be achieved via the coating 200 asdescribed in further detail below.

Optionally, the end effector body 102 may comprise a conductive materialsuch as a metal. Exemplary suitable conductive materials may include,without limitations, stainless steel, aluminum, nickel, copper,chromium, cobalt, molybdenum, ruthenium, tungsten, or platinum, forexample. Other suitable metals or alloys (e.g., aluminum alloy A16061)can also be used. A conductive end effector body (or another conductivechamber component) may also be coated with a coating 200 to create acoated end effector body (or another coated chamber component) that haselectrically-dissipative characteristics and may be able to supportelectrostatic discharge and avoid arcing and sudden conductive eventsbetween the end effector (or other chamber component) and/or waferthereon and/or other system components.

The term “semi-conductive” herein is meant to include the bulk materialof the particular component which exhibits semi-conductive electricalproperties as well as conductive or non-conductive bulk material that isrendered semi-conductive by, for instance, a coating of semi-conductivematerial or other semi-conductive electrical paths such as wiring,layers, ribbons, lines, or other electrical channels disposed thereon ortherethrough. Similarly, the term “conductive” herein is meant toinclude conductive bulk material or a semi-conductive or non-conductivematerial which is rendered conductive by a conductive coating or aconductive electrical path formed therethrough or thereon.

In some embodiments, the end effector 100 can be used at temperaturesbetween 150° C. to 650° C. In high temperature thermal processes, theremay be significant heat transfer between an end effector and a wafer inclose proximity. The thermal shock associated with heat transfer from analumina end effector to a wafer could potentially break a wafer. Incontrast, use of a transparent end effector, such as an end effectorcomprising quartz, would not relay such a dramatic thermal shock. Themitigated thermal shock that is observed with quartz end effectors isbelieved to be due to quartz not being as thermally conductive as aceramic (such as alumina) and due to quartz being transparent whichwould allow radiation to go through it (as compared to an opaque ceramicmaterial such as alumina).

In certain embodiments, quartz may be used as the material ofconstruction of end effectors used to transport substrates for hightemperature thermal processes since quartz creates minimal thermalshadow (said differently, quartz has a minimal thermal effect on awafer). Similarly, quartz may be used as the material of constructionfor other chamber components that would benefit from its minimal thermaleffect. In such embodiments, the coating may be transparent to maintainthe advantageous properties of a quartz end effector or of any otherquartz chamber component.

In certain aspects it may be advantageous for the coating to maintainsimilar properties (e.g., transparency) to those of the material ofconstruction of the underlying component. In other aspects it may beadvantageous for the coating to be independent with respect to certainproperties (e.g., resistivity performance) from those of the material ofconstruction of the underlying component.

Rapid movement of robots when transporting substrates may generateparticles. Static charge and the affinity for particles to gather oncharged surfaces (e.g., on a charged surface of an end effector bodycoupled to a robot's arm) are believed to be one of the contributors todefects on substrates. It is believed that by coating a surface of anend effector body (or of another chamber component that exhibits asimilar phenomenon) with an electrically-dissipative material, such ascoating 200, the charge can be released from the surface of the endeffector body (or of the other chamber component). This would allow theparticles to break free of van der vaals forces and re-distribute. Saiddifferently, the electrically dissipative material may provide adissipative path from the coating to the ground. The ability todissipate charge is believed to improve particle performance and defectperformance on a substrate. Additionally, the coating 200 and/or pads108 may provide an electrically-dissipative path between a supportedwafer and ground. If a wafer supported by the end effector 102 has anyresidual charge, that charge may be discharged via a path through thepads 108 and/or the coating 200.

Coated end effector bodies (and other coated chamber components) may bemanufactured with an electrically-dissipative material dopant to achievethe dissipation characteristics described above. However, manufacturingof doped components through bulk doping or slurry-based coating may becostly due to a variety of factors, such as, limited supply,manufacturing and yield issues, long lead time, and so on. Further,doped components may result in a brittle coating having a widedistribution of a range electrical surface/sheet resistivities acrossthe coated surface. The instant disclosure achieves the above describeddissipation characteristics by depositing a coating 200 on a top surfaceof an end effector body (or another chamber component) via an atomiclayer deposition (ALD) process, via a chemical vapor deposition (CVD)process, via an plasma enhanced atomic layer deposition (PEALD) process,via a metal organic chemical vapor deposition (MOCVD) process, or viamolecular beam epitaxy (MBE) process, some of which are described infurther detail with respect to FIGS. 4 and 5 . These processes may beadvantageous and cost effective as bare chamber components (such as bareend effector bodies) are more readily available, face less manufacturingand yield issues, have shorter lead times, and so on. Furthermore, aplurality of chamber components (such as a plurality of end effectorbodies) may be coated simultaneously (e.g., by inserting a plurality ofend effector bodies into the ALD, CVD, PEALD, MOCVD, or MBE depositionchamber). The resulting coating may also be more uniform, moreconformal, have lower porosity, be stronger, maintain its integritylonger, and have a narrower distribution of electrical surface/sheetresistivities across the coated surface, as compared to doped chambercomponents (such as end effectors) or chamber components (such as endeffectors) coated by slurry-based coating processes.

Coating 200 may comprise an electrically-dissipative material. Incertain embodiments, the coating 200 may also comprise a corrosionresistant material, which may be a plasma corrosion and/or erosionresistant material.

In some embodiments, the coating 200 may be a multilayer coating, whereat least one of the layers in the multilayer coating is an electricallydissipative layer comprising one of the aforementionedelectrically-dissipative materials, and wherein at least one other layerin the multilayer coating is a plasma resistant layer comprising aplasma resistant material.

In some embodiments, the coating 200 is a multilayer coating, and atleast one layer in the multilayer coating may comprise at least one ofaluminum oxide, yttrium oxide, zirconium oxide, Y₃Al₅O₁₂, a solidsolution of Y₂O₃—ZrO₂, a compound comprising Y₄Al₂O₉ and a solidsolution of Y₂O₃—ZrO₂, HfO₂, HfAlO_(x), HfZrO_(x), HfYO_(x), Hf dopedY₂O₃, zinc oxide, tantalum oxide, titanium oxide, erbium oxide,gadolinium oxide, lanthanum oxide, praseodymium oxide, neodymium oxide,promethium oxide, samarium oxide, europium oxide, terbium oxide,dysprosium oxide, holmium oxide, thulium oxide, ytterbium oxide, orlutetium oxide.

In some embodiments, the coating 200 is a multilayer coating, and atleast one layer in the multilayer coating may include Y₂O₃ and Y₂O₃based ceramics, Y₃Al₅O₁₂ (YAG), Al₂O₃ (alumina), Y₄Al₂O₉ (YAM), YF₃, SiC(silicon carbide), ErAlO₃, GdAlO₃, NdAlO₃, YAlO₃, Si₃N₄ (siliconnitride), AlN (aluminum nitride), TiO₂ (titania), ZrO₂ (zirconia), TiC(titanium carbide), ZrC (zirconium carbide), TiN (titanium nitride),Y₂O₃ stabilized ZrO₂ (YSZ), Er₂O₃ and Er₂O₃ based ceramics, Gd₂O₃ andGd₂O₃ based ceramics, Er₃Al₅O₁₂ (EAG), Gd₃Al₅O₁₂ (GAG), Nd₂O₃ and Nd₂O₃based ceramics, a ceramic compound comprising Y₄Al₂O₉ and asolid-solution of Y₂O₃—ZrO₂, a ceramic compound comprising Y₂O₃, Er₂O₃,ZrO₂, Gd₂O₃ and SiO₂, Hf based oxides and solid solutions, lanthanidebased oxides and solid solutions, or a combination of any of the above.

In some embodiments, the coating 200 is a multilayer coating, and atleast one layer in the multilayer coating comprises a solid solutionformed by any of the aforementioned ceramics. The coating 200 may alsoinclude a layer that may be a multiphase material that includes a solidsolution of one or more of the aforementioned materials and one or moreadditional phase.

With reference to the solid-solution of Y₂O₃—ZrO₂, a layer of thecoating 200 may include Y₂O₃ at a concentration of 10-90 molar ratio(mol %) and ZrO₂ at a concentration of 10-90 mol %. In some examples,the solid-solution of Y₂O₃—ZrO₂ may include 10-20 mol % Y₂O₃ and 80-90mol % ZrO₂, may include 20-30 mol % Y₂O₃ and 70-80 mol % ZrO₂, mayinclude 30-40 mol % Y₂O₃ and 60-70 mol % ZrO₂, may include 40-50 mol %Y₂O₃ and 50-60 mol % ZrO₂, may include 60-70 mol % Y₂O₃ and 30-40 mol %ZrO₂, may include 70-80 mol % Y₂O₃ and 20-30 mol % ZrO₂, may include80-90 mol % Y₂O₃ and 10-20 mol % ZrO₂, and so on.

With reference to a layer of the coating 200 comprising Y₄Al₂O₉ and asolid-solution of Y₂O₃—ZrO₂, in one embodiment the ceramic compoundincludes 62.93 molar ratio (mol %) Y₂O₃, 23.23 mol % ZrO₂ and 13.94 mol% Al₂O₃. In another embodiment, the ceramic compound can include Y₂O₃ ina range of 50-75 mol %, ZrO₂ in a range of 10-30 mol % and Al₂O₃ in arange of 10-30 mol %. In another embodiment, the coating 200 can includeY₂O₃ in a range of 40-100 mol %, ZrO₂ in a range of 0.1-60 mol % andAl₂O₃ in a range of 0.1-10 mol %. In another embodiment, a layer of thecoating 200 can include Y₂O₃ in a range of 40-60 mol %, ZrO₂ in a rangeof 35-50 mol % and Al₂O₃ in a range of 10-20 mol %. In anotherembodiment, a layer of the coating 200 can include Y₂O₃ in a range of40-50 mol %, ZrO₂ in a range of 20-40 mol % and Al₂O₃ in a range of20-40 mol %. In another embodiment, a layer of the coating 200 caninclude Y₂O₃ in a range of 80-90 mol %, ZrO₂ in a range of 0.1-20 mol %and Al₂O₃ in a range of 10-20 mol %. In another embodiment, a layer ofthe coating 200 can include Y₂O₃ in a range of 60-80 mol %, ZrO₂ in arange of 0.1-10 mol % and Al₂O₃ in a range of 20-40 mol %. In anotherembodiment, a layer of the coating 200 can include Y₂O₃ in a range of40-60 mol %, ZrO₂ in a range of 0.1-20 mol % and Al₂O₃ in a range of30-40 mol %. In other embodiments, other distributions may also be usedfor one or more layers of the coating 200.

In one embodiment, the coating 200 is a multilayer coating, and at leastone layer includes or consists of a ceramic compound that includes acombination of Y₂O₃, ZrO₂, Er₂O₃, Gd₂O₃ and SiO₂. In one embodiment, alayer of the coating 200 can include Y₂O₃ in a range of 40-45 mol %,ZrO₂ in a range of 0-10 mol %, Er₂O₃ in a range of 35-40 mol %, Gd₂O₃ ina range of 5-10 mol % and SiO₂ in a range of 5-15 mol %. In a firstexample, a layer of the coating 200 includes 40 mol % Y₂O₃, 5 mol %ZrO₂, 35 mol % Er₂O₃, 5 mol % Gd₂O₃ and 15 mol % SiO₂. In a secondexample, a layer of the coating 200 includes 45 mol % Y₂O₃, 5 mol %ZrO₂, 35 mol % Er₂O₃, 10 mol % Gd₂O₃ and 5 mol % SiO₂. In a thirdexample, a layer of the coating 200 includes 40 mol % Y₂O₃, 5 mol %ZrO₂, 40 mol % Er₂O₃, 7 mol % Gd₂O₃ and 8 mol % SiO₂.

Any of the aforementioned coating materials may include trace amounts ofother materials such as ZrO₂, Al₂O₃, SiO₂, B₂O₃, Er₂O₃, Nd₂O₃, Nb₂O₅,CeO₂, Sm₂O₃, Yb₂O₃, or other oxides.

In some embodiments, the coating 200 may comprise an alternating stackof a first material-containing layer and a second material containinglayer, as discussed above. The first material-containing layer maycomprise a single metal or metal alloy. Exemplary metal or metal alloysthat may be used for the first material-containing layer may includethose whose oxide is typically used as ceramic in bulk. In someembodiments, the first material-containing layer may comprise one ormore of Al, Zr, Y—Zr, Mg—Al, Ca—Al, or Si. The secondmaterial-containing layer may be a resistivity modifier such as, withoutlimitations, one or more of a transition metal, rare earth, main groupmetal, semiconductor, or an alloy thereof. In some embodiments, thesecond material-containing layer may comprise one or more of Ti, Fe, Co,Cu, Ni, Mn, V, Y, Nb, In, Sn, Fe—Co, or La—Ta.

In some embodiments, the first material-containing layer and thesecond-material containing layer may independently be an oxide,hydroxide, nitride, carbide, or metallic (i.e., have little to no oxygenor hydrogen or nitrogen or carbon). In one embodiment, the firstmaterial-containing layer and the second material-containing layer mayboth be in an oxide, hydroxide, nitride, carbide, or metallic form. Inanother embodiment, the first material-containing layer may have adifferent form from the second material-containing layer. For example,the first material-containing layer may comprise aluminum hydroxide(e.g., Al₂O_(2.99)H_(0.01) and the second material-containing layer maybe metallic Ti, TiN, SiC, metallic Al, and so on.

In some embodiments, the first material-containing layer may have afirst target thickness and the second material-containing layer may havea second target thickness. The ratio of the first target thickness tothe second target thickness may range from about 50:1 to about 1:50,from about 30:1 to about 1:30, from about 20:1 to about 1:20, from about10:1 to about 1:10, from about 10:1 to about 1:1, from about 8:1 toabout 1:1, from about 5:1 to about 1:1, from about 10:1 to about 2:1,from about 8:1 to about 2:1, from about 5:1 to about 2:1, or from about5:2 to about 1:1.

In one embodiment, the coating 200 may be alumina. In one embodiment,the coating 200 may be titania. In one embodiment, the coating 200 maybe a combination of alumina and titania, for example, an alternatingstack of alumina and titania. In one embodiment, theelectrically-dissipative material is a stack of alternating layers ofalumina and titania and the ratio of a thickness of each alumina layerto a thickness of each titania layer in the stack ranges from about 10:1to about 1:10. For example, the ratio of thickness may be from about 8:1to about 1:1, from about 5:1 to about 1:1, from about 10:1 to about 2:1,from about 8:1 to about 2:1, from about 5:1 to about 2:1, or from about5:2 to about 1:1. In one embodiment, the electrically dissipativematerial may be a stack of alumina and metallic titanium, or a stack ofaluminum hydroxide and metallic titanium, and so on.

For instance, FIG. 7A depicts an Energy Dispersive X-Ray Spectroscopy(EDS) line scan of a coating comprising a stack of alternating layers ofalumina and titania and FIG. 7B depicts a Transmission ElectronMicroscopy (TEM) image at 50 nm scale of the coating depicted in FIG.7A. In FIG. 7A, the atom % of oxygen is depicted by graphicalrepresentation 730, the atom % of aluminum is depicted by graphicalrepresentation 720, and the atom % of titanium is depicted by graphicalrepresentation 710. FIG. 7A illustrates that theelectrically-dissipative coating comprises well separated alternatingstacks of alumina and titania layers evidenced, in part, by wavygraphical representations 710 and 720 in the 30 nm to 130 nm range. Theelectrically-dissipative coating depicted in FIGS. 7A and 7B comprisewell-separated layers with each alumina (AlO_(x)) layer having athickness of about 5 nm and each titania (TiO_(y)) layer having athickness of about 2 nm. The ratio of the thickness of each aluminalayer to the thickness of each titania layer may be evidenced by theatomic percentage of aluminum compared to the atomic percentage oftitanium in the EDS line scan of FIG. 7A. The totalelectrically-dissipative coating has a thickness of about 100 nm. Theelectrically dissipative coating was deposited on a bulk alumina surfaceas evidenced in the EDS line scan of FIG. 7A in the 140 nm to 280 nmrange.

The coating 200 may be crystalline or amorphous and may uniformly andconformally cover the chamber component (e.g., end effector body) andany features thereon (such as contact pads 102) with a substantiallyuniform thickness. In one embodiment, the coating 200 has a conformalcoverage of the underlying surface that is coated (including coatedsurface features) with a uniform thickness having a thickness variationof less than about +/−20%, a thickness variation of less than about+/−10%, a thickness variation of less than about +/−5%, or a lowerthickness variation when comparing the thickness of the coating at onelocation to the thickness of the coating at another different location(or when assessing the standard deviation arising from a plurality ofthicknesses assessed at a plurality of locations). The TEM image in FIG.7B of an electrically dissipative coating according to an embodimentillustrates the uniform thickness of the coating across the entiredepicted surface.

The coating 200 may also have a substantially uniform electricalsurface/sheet resistivity or, in other words, a narrow distribution ofelectrical surface/sheet resistivities across the surface of thecoating. In some embodiments, the coating 200 has a uniform electricalsurface/sheet resistivity with an electrical surface/sheet resistivityvariation of less than about +/−35%, less than about +/−30%, less thanabout +/−25%, less than about +/−20%, an electrical surface/sheetresistivity variation of less than about +/−10%, an electricalsurface/sheet resistivity variation of less than about +/−5%, or a lowerelectrical surface/sheet resistivity variation when comparing theelectrical surface/sheet resistivity of the coating at one location tothe electrical surface/sheet resistivity of the coating at anotherdifferent location (or when assessing the standard deviation arisingfrom a plurality of surface/sheet resistivities assessed at a pluralityof locations).

For example, FIGS. 9A and 9B depict images of the front and back,respectively, of an exemplary end effector coated with a coatingaccording to an embodiment. The sheet resistance values measured in eachof the locations identified are summarized in Table 1 below.

TABLE 1 Sheet Resistance Distribution Across Front and Back Surfaces ofan Exemplary End Effector Coated with a Coating According to anEmbodiment Location Sheet Resistance (Ohm/square) 1 2.90E+06 2 3.60E+063 1.50E+06 4 2.20E+06 5 2.80E+06 6 2.60E+06 7 2.50E+06 8 3.40E+06 94.20E+06 10 2.90E+06 Average 2.86E+06 Standard Deviation 25%

In comparison, FIGS. 10A and 10B depicts images of the front and back,respectively, of an exemplary bulk-doped ceramic end effector. The sheetresistance values measured in each of the locations identified aresummarized in Table 2 below.

TABLE 2 Sheet Resistance Distribution Across Front and Back Surfaces ofan Exemplary Bulk-Doped Ceramic End Effector Location Sheet Resistance(Ohm/square) 1 2.60E+11 2 4.00E+07 3 2.20E+10 4 7.00E+10 5 2.00E+11 65.00E+07 7 1.80E+07 8 8.70E+11 9 1.40E+07 10 3.30E+07 Average 3.25E+10Standard Deviation 6E10%

The standard deviation in Table 1 and Table 2 is an indicator of theuniformity in sheet resistance values across various locations on an endeffector. The standard deviation in Table 2 illustrated significantnon-uniformity of the sheet resistance on the surface of bulk dopedceramic end effector. In comparison, coating an end effector inaccordance with embodiments described herein illustrated improved sheetresistance uniformity on the surface of the end effector. This may beevidenced by the smaller standard deviation in Table 1 and the narrowerdistribution of electrical surface/sheet resistivities across the coatedsurface.

Since the deposition processes described herein (ALD, CVD, PEALD, MOCVD,MBE) are very conformal processes, the coating 200 may have a roughnessthat matches the roughness of the underlying surface that is coated. Incertain embodiments, the coating 200 may have a surface roughness thatis about +/−20% or less, about +/−10% or less, or about +/−5% or less,as compared to the surface roughness of the underlying surface that isbeing coated. The coating described herein may be advantageous forcomponents that have high aspect ratios (e.g., aspect ratios of about3:1 to about 300:1, 20:1, 50:1, 100:1, 150:1, and so on), complexgeometric shapes, and three dimensional structures, as it uniformly andconformally coats the component's surface in its entirety including allcomplex features thereon.

For instance, a surface micrograph (not shown) of a sample coated with a50 nm thick alumina-titania nanolaminate having a 5 nm:2 nm ratio ofeach alumina layer thickness to each titania layer thickness and anelectrical surface/sheet resistance of about 1.6×10⁷ (per ASTM D-257method), according to an embodiment, illustrated that the coating isconformal, thin, crack-free, and follows the surface roughness of theunderlying alumina substrate.

This was further supported by top view Scanning Electron Microscope(SEM) images (not shown) of an undoped, bare alumina substrate and ananolaminate coated alumina substrate. The roughness of the undoped,bare alumina substrate was measured at 51±13 micro-inches. The roughnessof the nanolaminate coated alumina substrate was measured at 49±6micro-inches. The roughness measurements and the two SEM images showedthat the coating, according to embodiments described herein, at a 200 nmthickness, retained the underlying substrate's features and roughness.This data indicated that the mechanical properties of the underlyingsubstrate and feature shapes, on a sub-micron scale, were retained bythe thin and conformal coatings described herein.

The coating 200 may be very dense and have a very low porosity ascompared to other deposition techniques (such as e-beam IAD or plasmaspray). For instance, the coating 200 may have a porosity of less thanabout 1.5%, less than about 1%, less than about 0.5%, or about 0% (i.e.,porosity free). The term “porosity-free” as used herein means absence ofany pores, pin-holes, voids, or cracks along the whole depth of thecoating 200 as measured by transmission electron microscopy (TEM). Incontrast, with conventional e-beam IAD or plasma spray techniques ordoping or slurry-based coating, where the porosity may be 1-5% and insome instances even higher. The TEM image in FIG. 7B of an electricallydissipative coating according to an embodiment illustrates the highdensity and low porosity properties of the coating.

End effector body 102 (or other chamber components) may be coated with acoating 200 comprising a corrosion resistant material to withstandprocessing in corrosive plasmas. Non-limiting examples of corrosiveprocessing gases include halogen-containing gases, such as C₂F₆, SF₆,SiCl₄, HBr, NF₃, CF₄, CHF₃, CH₂F₃, F, Cl₂, CCl₄, BCl₃ and SiF₄, amongothers, and other gases such as O₂, or N₂O.

The resistance of the coating 200 to plasma may be measured through“etch rate” (ER), which may have units of Angstrom/min (A/min),throughout the duration of the coated components' operation and exposureto plasma. Plasma resistance may also be measured through an erosionrate having the units of nanometer/radio frequency hour (nm/RFHr), whereone RFHr represents one hour of processing in plasma processingconditions. Measurements may be taken after different processing times.For example, measurements may be taken before processing, after 50processing hours, after 150 processing hours, after 200 processinghours, and so on. An erosion rate lower than about 100 nm/RFHr, inhalogen plasma, is typical for a coating that is corrosion resistant.Variations in the composition of the coating 200 deposited on the endeffector body (or other chamber component) may result in multipledifferent plasma resistances or erosion rate values. Additionally, acoating 200 that is corrosion resistant with one composition exposed tovarious plasmas could have multiple different plasma resistances orerosion rate values. For example, a coating 200 may have a first plasmaresistance or erosion rate associated with a first type of plasma and asecond plasma resistance or erosion rate associated with a second typeof plasma.

The electrical surface/sheet resistance of the coating 200 may rangefrom about 1×10⁴ ohm/sq. to about 1×10¹² ohm/sq., from about 1×10⁴ohm/sq. to about 1×10¹¹ ohm/sq., from about 1×10⁵ ohm/sq. to about1×10¹¹ ohm/sq., from about 1×10⁴ ohm/sq. to about 1×10¹⁰ ohm/sq., fromabout 1×10⁴ ohm/sq. to about 1×10⁹ ohm/sq., from about 1×10⁴ ohm/sq. toabout 1×10⁸ ohm/sq., from about 1×10⁴ ohm/sq. to about 1×10⁷ ohm/sq.,from about 1×10⁴ ohm/sq. to about 1×10⁶ ohm/sq., from about 1×10⁴ohm/sq. to about 1×10⁵ ohm/sq., from about 1×10⁵ ohm/sq. to about 1×10¹⁰ohm/sq., rom about 1×10⁵ ohm/sq. to about 1×10⁹ ohm/sq., rom about 1×10⁵ohm/sq. to about 1×10⁸ ohm/sq., from about 1×10⁵ ohm/sq. to about 1×10¹¹ohm/sq., from about 1×10⁵ ohm/sq. to about 1×10⁶ ohm/sq., from about1×10⁶ ohm/sq. to about 1×10¹¹ ohm/sq., from about 1×10⁶ ohm/sq. to about1×10¹⁰ ohm/sq., from about 1×10⁶ ohm/sq. to about 1×10⁹ ohm/sq., fromabout 1×10⁶ ohm/sq. to about 1×10⁸ ohm/sq., from about 1×10⁶ ohm/sq. toabout 1×10⁷ ohm/sq., from about 1×10⁷ ohm/sq. to about 1×10¹¹ ohm/sq.,from about 1×10⁷ ohm/sq. to about 1×10¹⁰ ohm/sq., from about 1×10⁷ohm/sq. to about 1×10⁹ ohm/sq., from about 1×10⁷ ohm/sq. to about 1×10⁸ohm/sq., from about 1×10¹⁰ ohm/sq. to about 1×10¹² ohm/sq., from about1×10¹⁰ ohm/sq. to about 1×10¹¹ ohm/sq., or any other electricalsurface/sheet resistance in between these ranges, measured usingsurface/sheet resistance measurement system (such as, Prostat PRS-801with Probe PRF-912) pursuant to method ASTM D-257.

In certain embodiments, the electrical surface/sheet resistance of thecoating 200 may remain unchanged after being subjected to thermalcycling at a temperature ranging from about 150° C. to about 800° C.,from about 200° C. to about 750° C., from about 300° C. to about 700°C., from about 400° C. to about 600° C., or at about 500° C. In certainembodiments, the coating 200 may have electrical surface/sheetresistance after thermal cycling that is within about +/−35%, withinabout +/−30%, within about +/−25%, within about +/−20%, within about+/−10%, or within about +/−5%, as compared to the electricalsurface/sheet resistance of the coating 200 prior to thermal cycling.

In an embodiment where coating 200 comprises a 100 nm thick alumina andtitania nanolaminate coating on silicon (where the ratio of thethickness of each alumina layer to the thickness of each titania layeris about 5:2 and the coating was deposited using ALD at 200° C.), theelectrical surface/sheet resistance of the as deposited coating wasabout 9.53×10⁶ ohm/sq. After subjecting said coating to thermal cycling,the resistance of the coating was about 3.90×10⁶ ohm/sq. Thermal cyclingwas conducted by subjecting the coating to 400° C. in air five times fora duration of one hour each time. Specifically, the thermal cyclingprofile that said coating was subjected to was: a) temperature increaseat a rate of 10° C./min from 30° C. to about 400° C., b) coating held at400° C. for a duration of about 1 hour, c) temperature reduction to 60°C., d) cycles a) to c) were repeated four more times, e) finaltemperature reduction to 30° C.

Coating 200 may be resistant to thermal shock. The resistance to thermalshock may be evaluated by comparing the amount of cracks and electricalsurface/sheet resistance of an as-deposited coating to the amount ofcracks and electrical surface/sheet resistance of a coating that hasbeen subjected to thermal shock. A coating may be subjected to thermalshock by exposing it for about 10 minutes at 200° C. on a hot plate andthereafter dunking the heated coating into ice-water followed by airdrying. A coating that is resistant to thermal shock may have anelectrical surface/sheet resistance after thermal shock that is withinabout +/−35%, within about +/−30%, within about +/−25%, within about+/−20%, within about +/−10%, or within about +/−5%, of the electricalsurface/sheet resistance of the coating prior to thermal shock. Acoating that is resistant to thermal shock may be one that has no cracksprior to thermal shock and also has no cracks after having beensubjected to thermal shock.

For example, a nano-laminate coating of 5 nm:3 nm AlO:TiO (i.e., a ratioof each alumina layer thickness to each titania layer thickness being5:3) having a thickness of 100 nm was deposited on a quartz couponwithout any intermediate buffer layer between the quartz coupon and thecoating. The sheet resistance of this exemplary coating, as deposited,was 5.7 (±1.2)×E6 ohm/square. After subjecting the coated coupon to a200° C. shock test, the sheet resistance of the coating was 7.3 (±1)×E6ohm/square. This data illustrated that the resistivity performance ofthe exemplified coating was independent of that of the underlyingcomponent (or substrate, which in this example was the quartz coupon).This data also illustrated that the coating maintained an electricalsurface/sheet resistance after thermal shock that is at least withinabout +/−35% of the electrical surface/sheet resistance of the coatingprior to thermal shock.

In an embodiment where coating 200 comprises a 50 nm thick alumina andtitania nanolaminate coating (where the ratio of the thickness of eachalumina layer to the thickness of each titania layer is about 5:2), theelectrical sheet-resistance of the as deposited coating was about1.6×10⁷ ohm/sq. After subjecting said coating to thermal treatment at200° C., the resistance of the coating was about 1.90×10⁸ ohm/sq,measured according to ASTM D-257 method.

Coating 200 may be resistant to vacuum. The resistance to vacuum may beevaluated by comparing the electrical sheet resistance of coating 200outside of vacuum and in vacuum. A coating that is resistant to vacuummay have an electrical sheet resistance in vacuum that is within about+/−35%, within about +/−30%, within about +/−25%, within about +/−20%,within about +/−10%, or within about +/−5%, of the electrical sheetresistance of the coating prior out of vacuum. In an embodiment wherecoating 200 comprises an alumina and titania nanolaminate coating (wherethe ratio of the thickness of each alumina layer to the thickness ofeach titania layer is about 5:2 and the coating was deposited at 200°C.), the electrical sheet-resistance of the coating in vacuum at 298 K(or at 500K) is within about +/−20% of the electrical sheet resistanceof the coating outside vacuum at 298 K (or at 500K), as seen in FIG. 8 .

Coating 200 may have a Vickers hardness ranging from about 500 kg/mm² toabout 1000 kg/mm², from about 600 kg/mm² to about 900 kg/mm², or fromabout 700 kg/mm² to about 800 kg/mm². Coating 200 may have anindentation modulus ranging from about 100 GPa to about 300 GPa, fromabout 120 GPa to about 250 GPa, or from about 150 GPa to about 200 GPa.

In an embodiment where coating 200 comprises an alumina and titaniananolaminate coating on silicon (where the ratio of the thickness ofeach alumina layer to the thickness of each titania layer is 5:2 and thecoating was deposited at 200° C.), the Vickers hardness value is about791.88±50.55 kg/mm² and the indentation modulus is about 168.74±7.42GPa. The hardness and indentation modulus may be measured using a nanohardness tester at a temperature of about 21-23° C., using a maximumforce of about 0.5 mN, 1.0 mN, 2.0 mN, and 5.0 mN, a loading time ofabout 15 seconds, an unloading time of about 15 seconds, a pause time ofabout 10 seconds, with a Poisson's ratio of about 0.2, and an indenterID Berkovich Diamond.

In comparison, the Vickers hardness value of a 100 nm alumina depositedby ALD at 120° C. is about 510 kg/mm² and the Vickers hardness value ofa 100 nm titania deposited by ALD at 120° C. is about 127 kg/mm². Forα-alumina mineral, the Vickers hardness is about 1365 kg/mm² and elasticmodulus is about 370 GPa. For anatase titania mineral the Vickershardness is about 980 kg/mm² and the elastic modulus is about 230-290GPa.

Coating 200 may have composition purity of about 90% to about 100%,about 95% to about 99.9%, about 97% to about 99.8%, about 99% to about99.7%, or about 99.5%, measured by X-ray photoelectron spectroscopy.

Suitable thickness for the coating 200 may range from about 1 nm to 1000nm. In embodiments, the coating may have a maximum thickness of about750 nm, a maximum thickness of about 500 nm, a maximum thickness ofabout 400 nm, a maximum thickness of about 300 nm, a maximum thicknessof about 250 nm, a maximum thickness of about 200 nm, a maximumthickness of about 150 nm, a maximum thickness of about 100 nm, amaximum thickness of 50 nm, a maximum thickness of 30 nm, a maximumthickness of 20 nm, or another maximum thickness. In embodiments, thecoating 200 may have a minimum thickness of 5 nm, a minimum thickness of10 nm, a minimum thickness of 20 nm, a minimum thickness of 25 nm, aminimum thickness of 35 nm, a minimum thickness of 50 nm, a minimumthickness of 100 nm, a minimum thickness of 150 nm, or another minimumthickness.

Referring back to FIG. 1 , the end effector 100 may include threecontact pads 108. However, other embodiments may include other numbersof the contact pads 108. Contact pads 108 may be included on the endeffector body to minimize substrate sliding on the end effector bodyduring transport. To reduce sliding of the substrates, certain endeffectors comprise integrally-machined contact pads. Theintegrally-machined contact pads may have domed contact surfaces withsurface characteristics that contact and support the substrates and thatalso provide a low propensity for sliding. Each integrally-machinedcontact pad may have a machined contact surface with a particular domedprofile and surface roughness, which may reduce the likelihood of asubstrate sliding thereon. In some instances, wear of theintegrally-machined end effector contact pads and contamination thereofwith silicon particles/dust can increase the propensity of thesubstrates to slide on the contact pads and thus can limit the usefullife of the end effector. To prevent substrate sliding, the entire endeffector may be replaced periodically. In some embodiments, coating 200covers the contact pads 180. In some embodiments, the contact pads 180are composed of an electrically-dissipative material.

In certain embodiments of the present disclosure, replaceable contactpads are provided that can be rapidly changed out and replaced whenworn. Thus, the overall cost of continuing to provide a low slide endeffector may be dramatically reduced. An exemplary replaceable contactpad that may be disposed in end effector body 102 is shown in FIG. 3 .

As depicted in FIG. 3 , the bottom surface 102B of the end effector body102 may include a recess 214 formed therein. The recess 214 can becircular, and can extend into the end effector body 102 from the bottomsurface 102B to a depth HR. An aperture 215 may be formed in the endeffector body 102 and may extend between the top surface 102T and therecess 214. The recess 214 can have a recess diameter DR of from about 5mm to about 10 mm, and a recess height HR of from about 1.1 mm to about2.0 mm, for example. The aperture 215 can have an aperture DA diameterof from about 2.8 mm to about 4.8 mm, and an aperture height HA of fromabout 0.85 mm to about 1.1 mm, for example. Other diameters and heightsand depths can be used. Each may be larger for use with substrates of450 mm in diameter.

The contact pad 108 may include a contact pad head 208H having a contactsurface 210 that may be configured to contact the substrate 101. Thecontact surface 210 can include a domed shape. The contact surface 210can have a surface roughness of from about 45 μin Ra to about 65 μin Rameasured using a profilometer (such as Surfcorder SE-2300 equipmentcomplying to JIS standards). The contact pad head 208H can have acontact pad height HP of from about 1.0 mm to about 2.0 mm, for example.The contact pad head 208H can have a contact pad diameter DP of from 6.0mm to 12.0 mm, for example. Other suitable contact surface dimensions,profiles, radiuses, and surface roughness can be used.

The contact pad 108 may further include a shaft 212 coupled to thecontact pad head 208H and the shaft 212 may be received in aperture 215.Contact pad head 208H and the shaft 212 may be integrally formed as aone-piece component. The shaft 212 can further extend a distance fromthe underside 213 of the contact pad head 208H into the recess 214. Theshaft 212 may include a shaft indent 216 formed therein. The shaft 212should not extend below the bottom surface 102B of the end effector body102 so as not to interfere with substrate placement. The shaft indent216 may be provided in a form of a groove and may be formed in shaft 212at a location between the underside 213 of the contact pad head 208H andthe shaft end 212E of the shaft 212.

The shaft indent 216 may include a surface contour with an arcuatebottom. The circular securing member 218 may be received around theshaft 212 and may be seated in the shaft indent 216 to secure thecontact pad 108 to the end effector body 102. When the circular securingmember 218 is seated in the shaft indent 216, the circular securingmember 218 contacts a seating surface 214S of the recess 214 and also atleast a part of the shaft indent 216. In the depicted embodiment, thecircular securing member 218 comprises an O-ring that is compressedagainst the seating surface 214S in the as-installed condition. TheO-ring may be manufactured from an elastomer material, such as aperfluoroelastomer available as KALREZ® from DUPONT PERFORMANCEELASTOMERS, copolymers of hexafluoropropylene (HFP) and vinylidenefluoride (VDF or VF2) and available as VITON® from The Chemours Company,or any other suitable high-temperature elastomer. O-rings of elastomermay be used up to about 316° C.

Replaceable contact pad 108 configurations other than shown can be used.For instance, replaceable contact pads configured for high temperatureuse, such as from about 250° C. to about 650° C., or above about 320°C., may be used. In alternative embodiments, the shaft indent 216 maydiffer (e.g., in shape and/or dimensions and/or location), securingmember 218 may differ (e.g., in shape and/or dimensions and/or locationand/or material of constructions), any of the dimensions of any part ofthe contact pad may differ, the material of construction of the contactpad may differ, and so on.

In certain embodiments, the contact pad 108 can be made up of, include,or comprise any of the materials of construction listed above for theend effector body. For instance, in some embodiments, contact pad 108may comprise glass, quartz, ceramic, or a conductive material (such as ametal material). Exemplary ceramics may comprise bulk alumina,alumina-SiC composites, SiC, silicon nitride, boron nitride, and boron.Exemplary conductive materials may comprise stainless steel, aluminum,nickel, copper, chromium, cobalt, molybdenum, ruthenium, tungsten,platinum, or other suitable metals or alloys (e.g., aluminum alloyA16061).

The coating described above with respect to FIG. 2 could be deposited ona top surface of an end effector body (such as end effector body 102)and on a contact surface of a contact pad head (such as 208H) of acontact pad deposited in the end effector body.

FIG. 4 depicts one embodiment of a deposition process in accordance withan ALD technique to deposit a coating on an article, such as a chambercomponent (e.g., an end effector body with or without contact pads). Oneor more chamber components to be coated with any of the coatingsdescribed herein (e.g., one or more end effectors) may be placed incontrolled temperature-pressure deposition chamber prior to initiating aselected deposition process, such as ALD, CVD, PEALD, MOCVD, MBE, and soon.

Various types of ALD processes exist and the specific type may beselected based on several factors such as the surface to be coated, thecoating material, chemical interaction between the surface and thecoating material, etc. The general principle for the various ALDprocesses comprises growing a thin film layer by repeatedly exposing thesurface to be coated to pulses of gaseous chemical precursors thatchemically react with the surface one at a time in a self-limitingmanner.

FIG. 4 illustrates an article 110 having a surface. Article 110 mayrepresent a chamber component (such as an end effector body similar toend effector body 102 depicted in FIG. 1 ). For ALD, either adsorptionof a precursor onto a surface or a reaction of a reactant with theadsorbed precursor may be referred to as a “half-reaction.” During afirst half reaction, a first material-containing precursor (such asmetal-containing precursor) 160 is injected/pulsed onto the surface ofthe article 110 for a period of time sufficient to allow the precursorto fully adsorb onto the surface. The adsorption is self-limiting as theprecursor will adsorb onto a finite number of available sites on thesurface, forming a uniform, conformal, and continuous adsorption layer114 on the surface. Any sites that have already adsorbed a precursorwill become unavailable for further adsorption with the same precursorunless and/or until the adsorbed sites are subjected to a treatment thatwill form new available sites on the uniform, conformal, and continuouscoating. Exemplary treatments may be plasma treatment, treatment byexposing the adsorption layer to radicals, or introduction of adifferent precursor able to react with the most recent layer adsorbed tothe surface.

In some embodiments, two or more precursors are injected/pulsed togethersimultaneously or sequentially and adsorbed onto the surface of anarticle. The excess precursors are pumped/purged out with an inert gas.Thereafter a first reactant 165 (e.g., an oxygen-containingoxidizing/hydroxylating reactant, a nitrogen-containing reactant, acarbon-containing reactant and so on) is injected/pulsed to react withthe adsorption layer 114 to form a first material-containing layer 116(e.g., a first metal oxide layer or a multi-metal oxide layer). Firstmaterial-containing layer 116 may be uniform, continuous, conformal, andhave low porosity. Layer 116 may have a thickness of less than oneatomic layer to a few atoms in some embodiments after a single ALDdeposition cycle.

Multiple full ALD deposition cycles may be implemented to deposit athicker layer 116, with each full cycle (e.g., including introducingprecursor 160, flushing/purging, introducing reactant 165, and againflushing/purging) adding to the thickness by an additional fraction ofan atom to a few atoms. As shown, up to n full cycles may be performedto grow layer 116 until a first target thickness is achieved, where n isan integer value greater than 1. In embodiments, layer 116 may have afirst target thickness of about 5 angstroms to about 100 angstroms,about 10 angstroms to about 80 angstroms, or about 20 angstroms to about50 angstroms. In some embodiments, the first target thickness may rangefrom about 1 nm to about 1000 nm, from about 20 nm to about 500 nm, fromabout 20 nm to about 400 nm, from about 20 nm to about 300 nm, fromabout 20 nm to about 200 nm, from about 20 nm to about 100 nm, fromabout 50 nm to about 100 nm, or from about 20 nm to about 50 nm.

Subsequently, article 110 having first material-containing layer 116 maybe introduced to an additional precursor(s), such as secondmaterial-containing precursor (e.g., second metal-containing precursor)170 for a second duration to form a third half reaction and/or until asecond adsorption layer 118 is formed. Subsequently, article 110 may beintroduced to a second reactant 175 to react with adsorption layer 118to form a fourth half reaction and/or to grow second material-containinglayer 120. Layer 120 may be uniform, continuous, conformal, and have lowporosity. Layer 120 may have a thickness of less than an atom to a fewatoms (e.g., 2-3 atoms) after a single full cycle (e.g., includingintroducing precursor 170, flushing/purging, introducing reactant 175,and again flushing/purging). Multiple cycles may be implemented todeposit a thicker layer 120, with each cycle adding to the thickness byan additional fraction of an atom to a few atoms. As shown, the fullcycle may be repeated m times to cause the layer 120 to have a secondtarget thickness, where m is an integer value greater than 1. Inembodiments, layer 120 may have a second target thickness of about 1angstroms to about 50 angstroms, about 5 angstroms to about 30angstroms, or about 10 angstroms to about 20 angstroms. In someembodiments, the second target thickness may range from about 1 nm toabout 1000 nm, from about 20 nm to about 500 nm, from about 20 nm toabout 400 nm, from about 20 nm to about 300 nm, from about 20 nm toabout 200 nm, from about 20 nm to about 100 nm, from about 50 nm toabout 100 nm, or from about 20 nm to about 50 nm.

The full ALD deposition cycle may be repeated z times until a totaltarget thickness for the coating is achieved. The number of cycles z maybe represented by a fraction or an integer having a value greater than 1(e.g., 2-50, 5-30, 7-17, and any other number or range of numbers withinthese ranges). The total target thickness may range from about 1 nm toabout 1000 nm, from about 20 nm to about 500 nm, from about 20 nm toabout 400 nm, from about 20 nm to about 300 nm, from about 20 nm toabout 200 nm, from about 20 nm to about 100 nm, from about 50 nm toabout 100 nm, or from about 20 nm to about 50 nm. The final coating maycomprise a stack alternating layers of first material-containing layer116 and second material-containing layer 120.

The process described hereinabove of forming a stack of alternatinglayers may also be referred to herein as sequential deposition. OtherALD sequences, such as co-deposition or co-dosing may also be usedherein (e.g., by co-injecting multiple metal-containing precursors orsequentially injecting multiple metal-containing precursors prior tointroducing a reactant into the ALD deposition chamber).

After the stack of alternating layers has been formed, an anneal processmay be performed to cause the alternating layers of different materialsto diffuse into one another and form a complex coating (e.g., a complexoxide, a complex hydroxide, a complex nitride, a complex carbide, and soon) having a single crystalline/amorphous phase or multiplecrystalline/amorphous phases in some embodiments. After the annealingprocess, the stack of alternating layers may become a singleinterdiffused coating layer (not shown in FIG. 4 ). For example, if thelayers in the stack are Y₂O₃, Al₂O₃, and ZrO₂, then the resulting singleinterdiffused coating layer may be a ceramic compound comprising Y₄Al₂O₉and a solid-solution of Y₂O₃—ZrO₂.

The ratio of n cycles (for depositing the first material-containinglayers 116) tom cycles (for depositing the second material-containinglayers 120) may be designated as n:m. n:m may correspond to the ratio ofthe first target thickness of each layer 116 to the second targetthickness of each layer 120. n:m may also correspond to the compositionratio of the first material to the second material in coating 200.

In an embodiment, the coating 200 may be deposited on the top surface ofan end effector body 102T (or top surface of other chamber components)with an ALD process as described in FIG. 4 . The coating 200 maycomprise an electrically-dissipative material that is a stack ofalternating nano-layers 116 and 120 (also may be referred to herein asnanolaminates). The ratio of a thickness of each nano-layer 116 to athickness of each nano-layer 120 in the stack may range from about 50:1to about 1:50, from about 30:1 to about 1:30, from about 20:1 to about1:20, from about 10:1 to about 1:10, from about 10:1 to about 1:1, fromabout 8:1 to about 1:1, from about 5:1 to about 1:1, from about 10:1 toabout 2:1, from about 8:1 to about 2:1, from about 5:1 to about 2:1, orfrom about 5:2 to about 1:1.

The first target thickness of the first material-containing layers andthe second target thickness of the second material-containing layer mayindependently vary from one deposition cycle to another depositioncycle. For instance, one layer of the first material-containing layermay be 5 nm in thickness and another layer of the firstmaterial-containing layer may be 7 nm in thickness. Similarly, one layerof the second material-containing layer may be 2 nm in thickness andanother layer of the second material-containing layer may be 3 nm inthickness.

The deposition process temperature may correspond to the reactantcomposition in coating 200. In other words, the deposition processtemperature may determine the amount of oxygen, hydrogen, nitrogen,carbon, and so on in the coating 200. ALD processes may be conducted atvarious temperatures depending on the type of process. The optimaltemperature range for a particular ALD process is referred to as the“ALD temperature window.” Temperatures below the ALD temperature windowmay result in poor growth rates and non-ALD type deposition.Temperatures above the ALD temperature window may result in reactionstaken place via a chemical vapor deposition (CVD) mechanism. The ALDtemperature window may range from about 80° C. to about 500° C., fromabout 100° C. to about 400° C. In some embodiments, the ALD temperaturewindow is between about 100-300° C., or about 200° C.

The electrostatic dissipation of a chamber component (such as an endeffector body) coated with coating 200 may be a function of theelectrical surface resistivity (or sheet resistance) of the coating 200.The electrical surface/sheet resistivity of the coating 200 may be afunction of the composition of the coating (e.g., n:m ratio and reactantcomposition/content) and the thickness of the coating (determined by thenumber of full ALD cycles—z value). For instance, a 50 nm thickalumina-titania nanolaminate with a 5 nm:2 nm ratio of alumina layerthickness to titania layer thickness had an electrical sheet resistanceof about 1.6×10⁷ ohm/sq, a 100 nm thick alumina-titania nanolaminatewith a 5 nm:2 nm ratio of alumina layer thickness to titania layerthickness had an electrical surface/sheet resistance of about 9.4×10⁶ohm/sq, a 100 nm thick alumina-titania nanolaminate with a 5 nm:1 nmratio of alumina layer thickness to titania layer thickness had anelectrical sheet resistance of about 7.5×10⁷ ohm/sq, with all electricalsheet resistances being measured per ASTM D-257 method.

As may be understood from the ALD process described hereinabove, coating200 may be formed using an atomically precise, layer-by-layer approachto create nanolaminates with compositions and thicknesses that may becontrolled in the sub-nanometer range.

In one embodiment, layer 116 may be alumina and layer 120 may betitania. Exemplary aluminum-containing precursors that may be used todeposit an alumina layer include, without limitations, trim ethylaluminum (TMA), diethylaluminum ethoxide,tris(ethylmethylamido)aluminum, aluminum sec-butoxide, aluminumtribromide, aluminum trichloride, triethylaluminum (TEA),triisobutylaluminum, trim ethyl aluminum, or tris(diethylamido)aluminum.

Exemplary titanium-containing precursors that may be used to deposit atitania layer, include, without limitations,tetrakis(dimethylamido)titanium, tetrakis(ethylmethylamido)titanium,titanium tetrachloride, titanium ethoxide, titanium isopropoxide,methylcyclopentadienyl titanium isopropoxide, titaniumdimethylaminoethoxide isopropoxide variants,tris(dimethylamido)ethylcyclopentadienyl titanium, cycloheptatrienylcyclopentadienyl titanium, tris(methoxy)cyclopentadienyl titanium.

Other metal-containing precursors may be used depending on thecomposition of the coating 200.

Yttrium based coatings may be deposited by ALD using yttrium-containingprecursors such as, without limitations,tris(N,N-bis(trimethylsilyl)amide)yttrium (III), yttrium (III)butoxide,tris(cyclopentadienyl)yttrium(III), and Y(thd)3(thd=2,2,6,6-tetramethyl-3,5-heptanedionato).

Zirconium based coatings may be deposited by ALD usingzirconium-containing precursors such as, without limitations, zirconium(IV) bromide, zirconium (IV) chloride, zirconium (IV) tert-butoxide,tetrakis(diethylamido)zirconium (IV), tetrakis(dimethylamido)zirconium(IV), or tetrakis(ethylmethylamido)zirconium (IV).

Hafnium based coatings may be deposited by ALD using hafnium-containingprecursors such as, without limitations, HfCl₄, TEMAHf, TDMAHf, HfCpvariants, ZrCp variants.

Erbium based coatings may be deposited by ALD using erbium-containingprecursors that such as, without limitations,tris-methylcyclopentadienyl erbium (III) (Er(MeCp)₃), erbium boranamide(Er(BA)₃), Er(TMHD)₃, erbium(III)tris(2,2,6,6-tetramethyl-3,5-heptanedionate), andtris(butylcyclopentadienyl)erbium(III).

Exemplary oxidative reactants that may be used in the ALD process mayinclude, without limitations, oxygen, oxygen radicals, water, ozone,alcohol reactants, and the like. Other exemplary reactants that may beused in the ALD process to form the stack of electrically dissipativelayers may include, without limitations, reducing agents (H₂, H₂ plasma,metalorganic reagents such as aluminum hydride derivatives, silanes),nitriding agents (ammonia, amines, N₂), carburizing agents (alkanes),and the like.

In some embodiments, the coating 200 may be deposited on a surface of achamber component (e.g., an end effector body with or without contactpads) via a CVD process. An exemplary CVD system is illustrated in FIG.5 . The system comprises a chemical vapor precursor supply system 505and a CVD reactor 510. The role of the vapor precursor supply system 505is to generate vapor precursors 520 from a starting material 515, whichcould be in a solid, liquid, or gas form. The vapors may subsequently betransported into CVD reactor 510 and get deposited as a coating 525and/or 545 on the surface of article 530 (such as, top surface of endeffector body 102T), which may be positioned on article holder 535.

The coating depicted in FIG. 5 comprises a bilayer of layer 525 andlayer 545. It is understood by one of ordinary skill in the art thatalthough only a bilayer is exemplified with respect to the CVD process,a multilayer coating (such as a stack of more than two alternatinglayers) is also contemplated herein with respect to a CVD process. Amultilayer coating comprising a stack of alternating layers of aluminaand titania deposited by CVD are contemplated in certain embodimentsherein.

CVD reactor 510 heats article 530 to a deposition temperature usingheater 540. In some embodiments, the heater may heat the CVD reactor'swall (also known as “hot-wall reactor”) and the reactor's wall maytransfer heat to the article. In other embodiments, the article alonemay be heated while maintaining the CVD reactor's wall cold (also knownas “cold-wall reactor”). It is to be understood that the CVD systemconfiguration should not be construed as limiting. A variety ofequipment could be utilized for a CVD system and the equipment is chosento obtain optimum processing conditions that may give a coating withuniform thickness, surface morphology, structure, and composition.

The various CVD techniques include the following phases: (1) generateactive gaseous reactant species (also known as “precursors”) from thestarting material; (2) transport the precursors into the reactionchamber (also referred to as “reactor”); (3) absorb the precursors ontothe heated article; (4) participate in a chemical reaction between theprecursor and the article at the gas-solid interface to form a depositand a gaseous by-product; and (5) remove the gaseous by-product andunreacted gaseous precursors from the reaction chamber.

Suitable CVD precursors may be stable at room temperature, may have lowvaporization temperature, can generate vapor that is stable at lowtemperature, have suitable deposition rate (low deposition rate for thinfilm coatings and high deposition rate for thick film coatings),relatively low toxicity, be cost effective, and relatively pure. Forsome CVD reactions, such as thermal decomposition reaction (also knownas “pyrolysis”) or a disproportionation reaction, a chemical precursoralone may suffice to complete the deposition.

CVD has many advantages including its capability to deposit highly denseand pure coatings and its ability to produce uniform films with goodreproducibility and adhesion at reasonably high deposition rates. Layersdeposited using CVD in embodiments may have a porosity of below 1%, aporosity of below 0.1%, or be porosity free (e.g., 0% porosity).Therefore, it can be used to uniformly coat complex shaped componentsand deposit conformal films with good conformal coverage (e.g., withsubstantially uniform thickness). CVD may also be utilized to deposit afilm made of a plurality of components, for example, by feeding aplurality of chemical precursors at a predetermined ratio into a mixingchamber and then supplying the mixture to the CVD reactor system.

The CVD processes contemplated herein may utilize some of the precursorslisted above with respect to the ALD processes contemplated herein.

In certain embodiments, it may be preferred to deposit coating 200 usingan ALD process over a CVD process.

FIG. 6 illustrates an example embodiment of an electronic deviceprocessing tool 600 including a transfer robot 650 having an endeffector 100 supporting a substrate 101 (shown dotted for illustrationpurposes) wherein the substrate 101 is supported on contact pads(integral or replaceable). End effector 100 (with or without the contactpad deposited thereon) may be coated with an electrically-dissipativematerial using an ALD, a CVD, an PEALD, or an MBE process as describedherein. The electronic device processing tool 600 may include a numberof processing chambers 655 (shown dotted) coupled to a transfer chamber648. The transfer chamber 648 may house the transfer chamber (TC) robot650. The TC robot 650 may have a first arm 651, a second arm 652, and athird arm 653 (e.g., a robot wrist). The end effector 100 is coupled tothe third arm 653, such as through mounting plate 654. The end effector100 may contact and support a substrate 101 thereon (e.g., asemiconductor wafer, glass plate, etc.).

The transfer chamber 648 of the processing tool 600 may be connected,via one or more load lock chambers 656, to a factory interface 662. Thefactory interface 662 may house a factory interface (FI) robot 661. TheFI robot 661 may include an end effector (not shown, but substantiallyidentical to end effector 100) and that can have replaceable contactpads 108 as described herein and may be coated with anelectrically-dissipative material using an ALD or a CVD process asdescribed herein.

Substrate carriers 664 may be detachably connected to a front wall ofthe factory interface 662 and substrates 101 therein may be moved by theFI robot 661 between the substrate carriers 664 and the one or more loadlock chambers 656.

The processing tool 100 may be coupled to a controller 665. Thecontroller 665 may control movement of the substrates 101 and processingthereof. The controller 665 may include a central processing unit (CPU),support circuits, and a memory, for example. In operation, the TC robot650 may be operated, subject to commands from the controller 665, tomove substrates 101 between the various process chambers 655 and theload lock chambers 656 or between different process chambers 655, forexample.

As the manufacturing processes progress, the FI robot 661 and the TCrobot 650, working in tandem, may move substrates 101 between thesubstrate carriers 664 and the processing chambers 655. Variouselectronic device fabrication processes, e.g., semiconductor devicemanufacturing processes, such as, e.g., oxidation, thin film deposition,etching, heat treatment, degassing, cool down, etc., may take placewithin the process chambers 655.

Though TC chamber robot 650 is described as having an end effectorcoated with an electrically-dissipative coating, the FI robot 661 mayadditionally or alternatively include an end effector with anelectrically-dissipative coating.

In the foregoing description, numerous specific details are set forth,such as specific materials, dimensions, processes parameters, etc., toprovide a thorough understanding of the present invention. Theparticular features, structures, materials, or characteristics may becombined in any suitable manner in one or more embodiments. The words“example” or “exemplary” are used herein to mean serving as an example,instance, or illustration. Any aspect or design described herein as“example” or “exemplary” is not necessarily to be construed as preferredor advantageous over other aspects or designs. Rather, use of the words“example” or “exemplary” is simply intended to present concepts in aconcrete fashion. As used in this application, the term “or” is intendedto mean an inclusive “or” rather than an exclusive “or”. That is, unlessspecified otherwise, or clear from context, “X includes A or B” isintended to mean any of the natural inclusive permutations. That is, ifX includes A; X includes B; or X includes both A and B, then “X includesA or B” is satisfied under any of the foregoing instances. Referencethroughout this specification to “an embodiment”, “certain embodiments”,or “one embodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. Thus, the appearances of the phrase “anembodiment”, “certain embodiments”, or “one embodiment” in variousplaces throughout this specification are not necessarily all referringto the same embodiment.

The present invention has been described with reference to specificexemplary embodiments thereof. The specification and drawings are,accordingly, to be regarded in an illustrative rather than a restrictivesense. Various modifications of the invention in addition to those shownand described herein will become apparent to those skilled in the artand are intended to fall within the scope of the appended claims.

We claim:
 1. An end effector for a robot arm, comprising: an end effector body; and a coating deposited on a surface of the end effector body, the coating comprising an electrically-dissipative material, wherein the electrically-dissipative material is to provide a dissipative path from the coating to ground, wherein the coating is uniform, conformal, and porosity free, wherein the coating has a thickness ranging from about 20 nm to about 500 nm, and wherein the coating has an electrical resistance ranging from about 1×10⁵ ohm/sq to about 1×10¹¹ ohm/sq.
 2. The end effector of claim 1, wherein the electrical resistance of the coating remains unchanged after thermal cycling at a temperature ranging from about 300° C. to about 700° C.
 3. The end effector of claim 1, wherein the coating has a thickness ranging from about 20 nm to about 200 nm.
 4. The end effector of claim 1, wherein the end effector body comprises an electrically-conductive material, a ceramic, or quartz.
 5. The end effector of claim 4, wherein the end effector body comprises a conductive material that is a metal.
 6. The end effector of claim 4, wherein the end effector body comprises quartz and the coating is transparent.
 7. The end effector of claim 1, wherein the end effector body comprises a ceramic that is bulk alumina.
 8. The end effector of claim 7, wherein the electrically-dissipative material comprises alumina, titania, or a combination thereof.
 9. The end effector of claim 8, wherein the electrically-dissipative material comprises an alternating stack of alumina and titania.
 10. The method of claim 9, wherein a ratio of a thickness of each alumina layer to a thickness of each titania layer in the alternating stack of alumina and titania ranges from about 10:1 to about 1:1.
 11. The end effector of claim 1, wherein the coating is resistant to corrosive plasma.
 12. The end effector of claim 1, further comprising a replaceable contact pad disposed on the end effector body, the replaceable contact pad comprising a contact pad head having a contact surface configured to contact a substrate, and a shaft coupled to the contact pad head and received in an aperture formed in the body of the end effector and extending into a recess.
 13. The end effector of claim 12, wherein the coating is deposited on the surface of the end effector body and on the contact surface of the contact pad head.
 14. A method comprising: depositing a coating onto a surface of an end effector for a robot arm using an atomic layer deposition (ALD) process or a chemical vapor deposition (CVD) process, the coating comprising an electrically-dissipative material, wherein the electrically-dissipative material is to provide a dissipative path from the coating to ground, wherein the coating is uniform, conformal, and porosity free, wherein the coating has a thickness ranging from about 20 nm to about 500 nm, and wherein the coating has an electrical resistance ranging from about 1×10⁵ ohm/sq to about 1×10¹¹ ohm/sq.
 15. The method of claim 14, wherein depositing the coating using the ALD process comprises performing a deposition cycle comprising: injecting a first material-containing precursor into a deposition chamber containing the end effector body to cause the first material-containing precursor to adsorb onto the surface of the end effector body to form a first half-reaction; injecting a first reactant into the deposition chamber to form a second half reaction; repeating the injecting the first material-containing precursor and the injecting the first reactant one or more times until a first target thickness of a first material-containing layer of the coating is achieved; injecting a second material-containing precursor into the deposition chamber to cause the second material-containing precursor to adsorb onto the first material-containing layer to form a third half reaction; injecting a second reactant into the deposition chamber to form a fourth half reaction; and repeating the injecting the second material-containing precursor and the injecting the second reactant one or more times until a second target thickness of a second material-containing layer of the coating is achieved; and repeating the deposition cycle one or more times until the thickness ranging from about 20 nm to about 500 nm is achieved.
 16. The method of claim 15, wherein the coating comprises an alternating stack of alumina and titania, wherein the first material-containing precursor is an aluminum-containing precursor that comprises at least one of trimethylaluminum (TMA), diethylaluminum ethoxide, tris(ethylmethylamido)aluminum, aluminum sec-butoxide, aluminum tribromide, aluminum trichloride, triethylaluminum (TEA), triisobutylaluminum, trimethylaluminum, or tris(diethylamido)aluminum; wherein the second material-containing precursor is a titanium-containing precursor that comprises at least one of tetrakis(dimethylamido)titanium; wherein the first reactant and the second reactant comprises, independently, at least one of water, ozone, alcohol, and oxygen.
 17. The method of claim 16, wherein a ratio of a thickness of each alumina layer to a thickness of each titania layer in the alternating stack of alumina and titania ranges from about 10:1 to about 1:1.
 18. A substrate processing system, comprising: a chamber; a robot disposed in the chamber; and a robot arm connected to the robot, the robot arm comprising: an end effector body; a replaceable contact pad disposed on the end effector body, the replaceable contact pad comprising a contact pad head having a contact surface configured to contact a substrate, and a shaft coupled to the contact pad head and received in an aperture formed in the body of the end effector and extending into a recess; and a coating deposited on a surface of the end effector body and on the contact surface of the contact pad head, the coating comprising an electrically-dissipative material, wherein the electrically-dissipative material is to provide a dissipative path from the coating to ground, and wherein the coating is uniform and conformal.
 19. The substrate processing system of claim 18, wherein the end effector body comprises an electrically-conductive material, a ceramic, or quartz, wherein the coating has an electrical-resistance ranging from about 1×10⁵ ohm/sq to about 1×10¹¹ ohm/sq, wherein the coating has a thickness ranging from about 20 nm to about 500 nm, and wherein the coating is porosity free.
 20. The substrate processing system of claim 18, wherein the end effector body comprises bulk alumina, and wherein the electrically-dissipative material comprises an alternating stack of alumina and titania. 